Apparatus for controlling the tension in a running web



Feb. 23, 1960 G. DE GELLEKE APPARATUS FOR CONTROLLING THE TENSION IN ARUNNING WEB Filed Aug. 28, 1958 my 8x E 2 m m6 f United States PatentAPPARATUS FOR CONTROLLING THE TENSION IN A RUNNING WEB Gen-it DeGelleke, Parsippany, N.J., assignor'to Cameron llz tlaclhme Company,Dover, N.J., a corporation of New Application August 28, 1958, SerialNo. 757,729 5 Claims. (Cl. 242-7543) This invention relates to amechanism useful with or as a part of a web-winding machine formaintaining a substantially constant tension in a Web which is being runfrom a pay-out .roll to a take-up roll in such a machine to permitprocessing of the web as it moves between the two rolls. .Such tensioncontrol avoids or minimizes web breakage or damage which might occur'under excess or non-uniform tension conditions.

More particularly, the present invention relates to improved means fortaking advantage of the broad inventive principle disclosed in copendingapplication of Charles Aaron and Leonard Rockstrom, Serial No. 647,558,filed March 21, 1957. Said application discloses the principle ofutilizing torque variations which occurs at a motor which is employed todrive a Webwinding machine. Such torque variations occur substantiallyas tension variations occur in the web being run through such a machine.The present invention relates to improved means for utilizing suchtorque variations for controlling tension in the running web.

An important object of this invention is the provision of simplifiedmeans for utilizing torque variations at such a motor for controllingthe tension of the running web.

Another important object is the provision of means .responsive to suchtorque variations which, where belt transmission is employed between themotor and the machine, involves only a minor revision in thebelttransmission means. 1

Another important object is the provision of such torque-responsivemeans which gives broader latitude as to the type and size of motorWhich may be used.

Another important object is the provision of such torque-responsivemeans which are separate .from the motor itself but which may be easilyadapted for use with different sizes of motors and for machines forWinding different types of materials.

Another important object is the provision of such torque-responsivemeans which avoids the need for providing a floating type of mount forthe motor such as is disclosed in the mentioned copending application.

Another important object is the provision of such torque-responsivemeans wherein the response from torque at the motor is of increasedmagnitude, thereby providing a mechanism which is simpler and easier toadjust and service.

Another important object is the provision of such torque-responsivemeans which react more rapidly to web-tension variations than theapparatus disclosed in the said copending application.

Another important object is the provision of such torque-responsivemeans which function as a cushion or shock absorber between the motorand the winding machine to reduce the possibility of encountering suddenchanges in web tension due to sudden changes in motor torque or speed.

The foregoing and other more or less obvious advantages and objects arederived from the present invention of which a preferred embodiment isshown in the accom- 2,925,963 Patented Feb. 23, 1960 panying drawing forillustrative purposes without, however, limiting the invention to theparticular apparatus disclosed in said drawing.

The drawing is a more or less diagrammatic view of a preferred form ofweb-tension-controlling apparatus according to this invention; thearrangement of the components of the invention being such as tofacilitate an understanding of the invention without regard .to theparticular location of some of the components in prac- 'tice and withoutregard to the particular location of piping that would be employed in anactual installation. Also, no attempt has been made to show thecomponents in their actual relative sizes.

The illustrated apparatus comprises a pay-out roll 10 and a take-up roll12, a pair of driving rollers 14 and 16, guide rollers 18 and 20 and acutting mandrel 22 between which and a circular cutting knife 24 a web Wpasses in running from pay-out roll 10 to talke-up roll 12 in theprocess of being slitted into two separate webs each about half of thewidth of the original web.

The web may be of paper, cellophane, or other plastic, or metal foil or,indeed, any type of web material. The showing of the cutting mandrel 22and the cutting knife 24 is only to indicate that the purpose of passingthe web from roll 10 to roll 12 is merely to process it in some manner.The processing need not necessarily be slitting, but it may be in theform of printing or glazing the surface of the web or otherwiseprocessing the web.

All the mentioned rolls and rollers are so mounted in the frame of themachine that they may turn on parallel axes. In .a strict sense, thepart of the machine constituting the take-up roll 12 may be merely ashaft or thin drum 26, and the pay-out roll 10 may be merely a'shaft 28with which is associated a suitable brake .device 30. In this sense, theindicated rolls 10 and 12, therefore, are largely rolls of web material.Except where essential to an understanding of the invention, shafts andsupporting framework have been omitted, as the type, disposition, andconventional manner of supporting such parts are well known to thosefamiliar with this art.

The web W is caused to move from pay-out roll 10 to roll 12 to become apart of the latter by the 'driving rollers 14 and 16, which are turnedby a suitable motor 32 through a main driving belt 34, working on asingle pulley 36 on the shaft of the motor and one sheave of a doublepulley 38, and a torque-responsive driving belt 40 which works in theother sheave of said double pulley and in sheaves suitably provided onrollers 14 and 16. Between the pulley 38 and the pulleys on rollers 14and 16, the torque-responsive driving belt passes about variousstationary and movable guide pulleys as hereinafter described.

The shaft or thin drum 26 is a floating shaft which, with the roll 12 ofaccumulating web material, is supported upon and turned frictionally bythe two rollers 14 and 16. The brake device 30, as illustrated, consistsof brake-arms 44, 46 pivoted at their lower ends at fixed points andlinked together toward their upper ends by a fiuid-pressure-operatedassembly consisting of a cylinder 48 pivoted to brake-arm 46 and apiston '50, within said cylinder, having a rod 52 extending through oneend of said cylinder and pivoted to brake-arm 44.

The brake-arms 44 and 46 are fitted with suitable brake shoes 54, whichengage shaft 28 to exert a braking force upon the latter. The upper endsof the brake-arms 44 and 46 are normally urged apart, tending to relievethe pressure or contact of the brake-shoes with respect to the shaft 28,by means of a compression coil spring 56, which extends about a rod 58,one end of which is pivoted to arm 44, and the other end of whichextends 3 slidably through the upper end of arm 46. The spring 56 iscompressed between the arm 46 and a collar 60 fixed upon rod 58 at apoint near arm 44.

It is well understood that tension in a running web in a winding machinearises from the fact that some opposition is presented to the withdrawalof web from the pay-out roll 10. The just-described braking deviceconstitutes such opposition and the tension present in the running webdepends largely upon the extent of such opposition presented by saidbraking device. Also, it should be understood that if the tension in therunning web should at any time rise above or fall below approximatelythe tension desired in said web, the undesirable higher or lower tensionmay be rectified by suitable variations in the applied braking effect.

According to this invention, such variations in the applied brakingeflect are brought about through various instrumentalities which areresponsive to variations in the torque at the motor 32. If the webtension increases, the increase will be reflected in an increase in thetorque at the motor, while if the web tension decreases, the decrease,likewise, will be reflected in a decrease in the torque at the motor.This invention includes an arrangement now to be described, whereby,such variations in the torque at the motor are utilized to control theoperation of the braking device 30 and thereby control the tension inthe running web to keep it substantially at the tension which is desiredto be mained throughout a run of web material through the windingmachine.

The brake mechanism 30 is operated by fluid pressure from a suitablesupply source of pressurized air or other suitable fluid which isconducted by pipe 62 from said fluid supply to afluid-pressure-regulating valve 64, thence through a pipe 66 to the areawithin brake cylinder 48 which is in back of or to the left of thepiston 50. The regulating valve 64 is one in which endwise movement of aplunger 68 causes variations in the fluid pressure delivered to thebrake cylinder 48. When the plunger 68 moves inwardly with respect tovalve 64, the pressure delivered to the brake cylinder is increased, andwhen the plunger 68 moves outwardly with respect to the valve 64, thepressure delivered through the latter to the brake cylinder 48 isreduced.

The plunger 68 is operated by a cam 70, an arm 72 of which is pivotallyconnected by an adjustable link 74 to the end of one arm 76 of a bellcrank 78 which pivots at point 80 on a bracket 82 suitably mountedwithin or on the casing of the winding machine. The other arm 84 of thebell crank 78 is formed with a segmental extension 86 on its free endserving as a means for carrying two movable belt-guide rollers 88 and 90which, with stationary but rotatable guide rollers 92, 94, 96, 98 and100, serve to guide the belt 40 in a circuitous movement between thedouble pulley 38 and the driving rollers 14 and 16, as illustrated inthe drawing. The rollers 88 and 90 are mounted on the segmentalextension 86 by suitable stub shafts, and the just-enumerated stationaryguide rollers 92, 94, 96, 98 and 100 are similarly mounted by suitablestub shafts upon an adjacent portion of the frame of the windingmachine.

The right of free end of the segmental extension 86 is pivotallyconnected to one end of a piston rod 102 which extends into the upperend of a fluid-pressure cylinder 104. Within the cylinder is a piston106 suitably fixed on the inner end of the piston rod 102. The cylinder104 is suitably vented as at 108 at a point above the piston 106 and thelatter partially defines below it a pressure chamber 110 within saidcylinder. Fluid pressure is suitably supplied to the chamber 110 fromthe source of supply of pressurized fluid by means of a pipe 112 whichis connected to the pipe 62 and to one side of a hand-operablepressure-regulating valve 114. Pressure fluid passing from the pipe 112into and through the valve 114 is carried by a pipe 116 into thepressure chamber 110. A suitable pressure gauge 118 is preferablyconnected in the pipe 116 so that an operator by turning handwheel 120of valve 114 may control the pressure flow through the latter to thechamber 110 and by means of the gauge 118 may be informed as to thepressure in that chamber and, when proper operation is achieved, mayknow the pressure which may advantageously be used in some later,similar operation of the apparatus.

It may be noted that the brake cylinder 48 is pivotally supported onbrake arm 46 and that cylinder 104 is pivotally mounted at pivot point122 upon a bracket 124 suitably fixed to some stationary part of thewinding machine. It may also be noted that the link 74 is in two partswhich are slidably interconnected and held together by adjusting screws126 so that the length of the link 74 may be adjusted to that lengthwhich will function best to achieve the desired operation.

In operation, valve 114 is manually adjusted to deliver fluid to thecylinder 104 at such pressure as to cause the piston 106 and the pistonrod 102 to push the segmental extension 86 leftwardly to its conditionas illustrated in the drawing, at which point the belt 40, in engagementwith the guide rollers 88 and 90, limits the extent to which saidsegmental extension 86 may move leftwardly. If the motor 32 were not inoperation when the pressure was thus applied in cylinder 104, it wouldbe possible for the segment 86 to move leftwardly somewhat more thanshown in the drawing. However, when the motor is in operation, thetorque at the motor operating through the belt to turn the rollers 14,16 and the take-up roll 12 tends to provide a loop of the belt 40 aboutthe guide roller and to shorten somewhat the loop of the belt aroundguide roller 88 approximately to the condition of the belt shown in thedrawing. Thus, the drawing is approximately illustrative of thepositions of the guide rollers 88 and 90 when the machine is inoperation.

It will be seen that with an increase in tension in the running web,there will be an increase in torque at the motor 32 and this increase intorque tends to equalize the sizes of the loops of belt 40 at guiderollers 88 and 90, which tendency is opposed by the fluid pressureestablished in pressure chamber 110. The arrangement is such that, afterestablishment of such a fluid pressure in chamber as will give rise toand maintain the desired tension in the web, any variation of thetension, as the web runs through the machine, causes the motor torque,operating through the belt 40 in opposition to the pressure in chamber110, to shift the segmental extension 86 to reestablish the web tensionas it existed before such variation.

The reestablishment of the web tension occurs as a result of thementioned pivotal movement of the segmental extension 86. Thus, if thetension variation is an increase, the resultant increased torque at themotor 32 causes the belt 40 to shift the segmental extension 86rightwardly, as viewed in the drawing, which causes bell-crank arm 76,through link 74, to turn the cam 70 counterclockwisely. The efiect ofthis movement of the cam is to permit plunger 68 to move slightlyoutwardly with respect to valve 64, thereby decreasing the fluidpressure controlled by that valve and communicated to brake cylinder 48.The decrease in fluid pressure in cylinder 48 has the eifect of enablingspring 56 to reduce the braking effect of the brake shoes 40 upon shaft48; and, this reduction in the braking effect results in termination ofthe undesired increase in the web tension.

If the variation in the web tension is a decrease, there would occur acorresponding decrease in the torque at the motor 32, with the resultthat belt 40 would have only a somewhat reduced tendency to oppose thefluid pressure in chamber 110. Under that condition, the fluid pressurein said chamber would urge the segmental extension 86 leftwardly ofvalve 64, thereby permitting communication of increas d flui Pressure tobrake y inder 48, the efiect of which would be to increase the brakingeffect on shaft 28 and thereby increase the web tension to terminate theundesired decrease in the webv tension.

It should be understood that the concepts disclosed and explained hereinmay be utilized in various other ways without departing from the presentinvention.

I claim:

1. Apparatus for controlling tension in a running web moving from apay-out roll to a take-up roll, comprising braking means disposed inbraking relation to said web and coacting with the latter to opposemovement of the web toward the take-up roll, a motor, a transmissionbelt coacting with said motor and said take-up roll to rotate thelatter, a guide-supporting member movable transversely across oppositecourses of said belt, a pair of guide elements on said member arrangedto engage and oppositely deflect said opposite courses and to tendtoward equal deflection at said courses in response to torque of saidmotor transmitted by said belt, yieldable deflectonaltering means urgingsaid member in one direction in opposition to said tendency, whereby toestablish unequal deflection at said courses, and control means,responsive to movements of said member, caused by such torque, forcontrolling said braking means.

2. Apparatus according to claim 1, said braking means being connected tosaid pay-out roll.

3. Apparatus according to claim 1, said deflectionaltering meanscomprising a fluid-pressure cylinder.

.4. Apparatus according to claim 1, said braking means being fluidoperated and said control means comprising a connection between a sourceof fluid and said braking means and a fluid-regulating device in saidconnection, operable in response to movement of said member, forcontrolling the delivery of fluid to said braking means.

5. Apparatus according to claim 1, said braking means beinghydraulically operated and said control means comprising a pipeconnection between a source of fluid and said braking means and aregulating valve in said pipe connection, operable in response tomovement of said member, for controlling the delivery of fluid to saidbraking means.

References Cited in the file of this patent UNITED STATES PATENTS2,164,596 Simonds July v4, 1939 2,460,694 Haswell Feb. 1, 1949 2,733,876Laycock Feb. 7, 1956 UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent No. 2,925,963 February 23, 1960 Gerrit De Gelleke Itis hereby certified that error appears in the-printed specification ofthe above numbered patent requiring correction and that the said LettersPatent should read as corrected below.

line 62, for "of", first occurrence, read or Column 3 1 deflector" readdeflection column 5 line 21 for Signed and sealed this 16th day ofAugust 1960.

( SEAL) Attest:

KARL Ho AXLINE Attesting Officer ROBERT C. WATSON Commissioner ofPatents

